These are live pictures. We'll bring you any new developments as they unfold.

Plus, cracking the hacking. Was Russia behind the e-mail leak and the turmoil that followed inside the Democratic Party? We'll take a closer look at all the new evidence.

Anderson will join us shortly. I'm Wolf Blitzer. We're in Philadelphia and you're in THE SITUATION ROOM.

Good evening and get ready. The Democratic Party, this is their convention. It is now underway, officially gaveled into session, not by the party chairwoman, who was forced out yesterday, they practically booed off the stage by her own Florida delegation this morning. Party hoping the acrimony going in -- will yield through unity throughout the week and taking some immediate steps as we speak right now.

More on the booing his supporters gave him in just a moment. First I want to go to our chief political correspondent Dana Bash. She's joining us from the convention floor right behind me with new efforts to try to contain the acrimony.

Dana, as you know, the Democratic Party has just issued a formal apology, a public apology, to Senator Sanders. What more can you tell us?

DANA BASH, CNN CHIEF POLITICAL CORRESPONDENT: This happened not long after this convention formally gaveled open and it is a statement from Donna Brazile, who is now the interim chair of the party, and other officers, saying, "On behalf of everyone at the DNC, we want to offer a deep and sincere apology to Senator Sanders, his supporters, and the entire Democratic Party for the inexcusable remarks made over e-mail. These comments do not reflect the values of the DNC or our steadfast commitment to neutrality during the nominating process."

And going on to say that they are committed to not being disrespectful. Clearly trying to get a handle on what is still a very, very deep discontent and discord. And that obviously goes beyond this e-mail scandal. I mean, it comes from a year plus of a very, very intense debate and hard fought primary and caucus season between Bernie Sanders and Hillary Clinton. And Bernie Sanders, he still has delegates who are on this floor who are incredibly passionate.

I'm standing here in the Nevada delegation, Wolf, who came up the steps because when Marcia Fudge, one of the officers, a congresswoman, started to do some business at the podium, you heard these people here screaming, Bernie, Bernie, Bernie, and boo, booing them, and as you can see holding up "Stop TPP" signs which is of course the trade pact which most Bernie Sanders supporters think is absolutely horrible.

And now we do see Hillary Clinton and have seen Hillary Clinton say that she is distancing herself from that. But it just kind of illustrates to you the very deep divide still here among Bernie Sanders supporters and Hillary Clinton supporters even as Bernie Sanders himself tries to calm people down as this convention gets under way.

BLITZER: All right, Dana, stand by. I want to continue our coverage. Bernie Sanders and the moment, we're calling it now, before this apology from the DNC that really underscored those deep divisions here. His stated mission to persuade the people who voted for him to vote for Hillary Clinton. He got a dress rehearsal earlier today.

Speaking to supporters, he walked them through what he sees as their accomplishment during the campaign and his goals for the future. He got standing ovations until, until he mentioned the winning ticket.

SANDERS: Brothers and sisters. Brothers and sisters. This is -- this is the real world we live in.

(END VIDEO CLIP)

BLITZER: More now on that truly remarkable moment today and efforts now under way to try to avoid a repeat tonight or worse.

[17:05:07] CNN's Jeff Zeleny is with me. He's got some new reporting.

They are working together now, the Clinton campaign and Bernie Sanders to try to avoid the booing.

JEFF ZELENY, CNN SENIOR WASHINGTON CORRESPONDENT: They are indeed, Wolf. And that was a big precursor to what they're fearing is taking place here. Bernie Sanders sent a text message directly to his own supporters.

Let's take a look at this message that his delegates are receiving. It says, "I ask you as a personal courtesy to me to not engage in any kind of protest on the floor. It's of utmost importance you explain this to your delegations." Signed, "Bernie." But unclear that that message was read or certainly unclear if it was effective at all because we heard so many boos and jeers for a variety of things, as Dana said, TPP. Also the mention of Tim Kaine just elicited many boos.

But the former mayor of Denver, Wellington Webb, just moments ago behind us on the floor said they both deserve our cheers. They both deserve our cheers. That's what they are trying to do here to unify people. But I think there's a big worry here among the Clinton side that this will happen all night.

BLITZER: What should we expect tonight when Bernie Sanders speaks? Will it be a pro Hillary Clinton speech or an anti-Donald Trump speech?

ZELENY: Wolf, if it's any indication, the speeches he's given before up until this point, it will be an anti-Donald Trump speech. He has not really ever given a full throated forceful speech supporting her and why. But it'll be interesting to see if that changes because the one this afternoon that you and I were watching earlier today was certainly this anti-Donald Trump. But the Sanders campaign is working with the Clinton people to try and calm this crowd. He started this revolution. We'll see if it continues to be on this week here in Philadelphia.

BLITZER: We will soon find out. Jeff, thank you very much.

Surrounding all of this tonight, global intrigue unfolding right now. Hacked e-mails, embarrassing to the Democratic National Committee, making their way on to WikiLeaks, they're now to the convention run- up. It raises all kinds of serious questions including one that's troubling as it is unprecedented, namely, is Russia somehow trying to manipulate the outcome of this U.S. election? That's the question.

Joining us now with some new late-breaking developments, our justice correspondent Evan Perez.

Evan, you're getting new information that the feds warned the DNC about a possible hack. What's the latest information you're learning?

EVAN PEREZ, CNN JUSTICE CORRESPONDENT: That's right, Wolf. I'm told that federal investigators tried to warn the DNC about a potential intrusion in their computer network months before the party moved to try to fix the problem. Now this raises new questions about whether the DNC could have done more to limit the damage that was done by hackers that are suspected of working for the Russian intelligence agencies.

Now the DNC did bring in consultants from a -- from the private security form CrowdStrike in April and by the time the suspected Russian hackers were kicked out of the DNC network in June, the hackers had been in the system for about a year. Now I talked to someone who was briefed on the DNC's response and they tell me that the warning from the FBI and from other agencies wasn't very specific and that the extent of the problem wasn't clear.

It's not even clear that they talked to the right person, Wolf. We do know that DNC officials did hire outside help after they saw additional indications that their system was compromised.

BLITZER: And that's pretty shocking to hear that, Evan. That these hackers could have been in the -- the DNC e-mail system for a year, for a whole year? Is that right?

PEREZ: That's right, Wolf. They had the run of the system for about year. That's taking a look at everything and they can tell from all the different parts of the network that they're at, and, you know, so far, from the evidence that we've seen, that the investigators have seen, they believe that this points to at least one group of hackers that is familiar to U.S. counter intelligence.

Now this is the same group that was involved in hacking into the non- classified e-mail systems at the State Department and at the White House and at other federal agencies. Now the DNC breach occurred around the same time as the breaches of those government systems and analysts from the NSA found signatures in those breaches that led them to other intrusions, including at the DNC -- Wolf.

BLITZER: And, Evan, what are you hearing about the timing of all of this? These, you know, very embarrassing e-mails released on the eve of this convention.

PEREZ: Well, that's really what gives everyone suspicion, frankly, that Russian intelligence is behind this, behind this attack. We also -- they also believe, by the way, that they are behind a wave of other cyber attacks against political organizations and even think tanks here in Washington, Wolf. You know, the question for investigators is, is this an indication that Russian intelligence was trying to sway the U.S. election? That's at the top of the mind of these investigators now -- Wolf.

BLITZER: The suspicion of the Clinton campaign that they think the Russians are trying to influence it in favor of Donald Trump.

[17:10:04] All right, Evan. Thank you very much.

Up next, Anderson and the panel, talking about all of this, about Bernie Sanders supporters, whether they'll follow him when he endorses the winning ticket.

The big speeches tonight and a whole lot more.

And later, the Trump post-convention bump. What new polling says about the challenges facing Hillary Clinton this week. As our day one Democratic National Convention coverage continues.

[17:15:04] We're about an hour and 15 minutes into the Democratic National Convention surrounded for now at least with contention, controversy and possibly Cold War-style international intrigue.

A Sanders delegate on stage right now. Let's listen in.

UNIDENTIFIED FEMALE: It was mostly about democratizing our party for generations to come.

(CHEERS AND APPLAUSE)

UNIDENTIFIED FEMALE: And it may be hard, and believe me it may be messy, but, ladies and gentlemen, this is what democracy looks like.

(END VIDEO CLIP)

COOPER: All right. Joining now, our big named panel, CNN chief political correspondent and "INSIDE POLITICS" anchor John King, our senior political reporter Nia-Malika Henderson, Sirius XM Radio talk show host and anchor of CNN's "SMERCONISH," Michael Smerconish. He's a child of nearby Doylestown, Pennsylvania. Also chief political analyst Gloria Borger. Former Philadelphia mayor, Michael Nutter, a Clinton supporter, plus a Sanders supporter and talk radio host, Bill Press. And Democratic superdelegate and former New York City council speaker, Christine Quinn. And Trump supporters Andre Bauer, former lieutenant governor of South Carolina.

This is certainly probably not the way she -- the DNC planned this convention to start off, John King. I mean, we have seen not only the controversy over the e-mails, we've seen Debbie Wasserman Schultz refusing to not appear here, and then agreeing to not appear here after she was booed this morning. And demonstration in the streets. And Sanders getting booed when he talked about supporting Hillary Clinton.

JOHN KING, CNN CHIEF NATIONAL CORRESPONDENT: And now reliving the campaign debate over superdelegates as they have this platform discussion here in which the Sanders campaign actually won some key concessions. Donna Brazile, our former colleague, now about to be the interim chair of the party, I was talking to her yesterday as all this is breaking out. She said we watched a messy Republican convention last week where they tried to be Democrats. Now we're going to really show them how Democrats be Democrats.

(LAUGHTER)

NIA-MALIKA HENDERSON, CNN SENIOR POLITICAL CORRESPONDENT: Yes.

KING: About, what, 43 percent of the people in this room are Bernie Sanders supporters. They were coming a little agitated anyway. At the end of the primary season, the younger ones especially, think this didn't work right. They always suspected the system was rigged. Then this e-mail story breaks and it's just -- it's not logs on the fire. It's just like gasoline trucks.

COOPER: So what happens tonight when Bernie Sanders speaks? I man, there is a real effort now on the floor. They -- Jeff Zeleny was reporting the Sanders supporters, the whips, the Clinton supporters, the whips said sort of unified to try to get people to basically not boo Hillary Clinton during Sanders' speech.

GLORIA BORGER, CNN CHIEF POLITICAL ANALYST: I don't see how they keep it from happening, honestly.

HENDERSON: Yes.

BORGER: I mean, these are people and maybe Bill Press can talk about it, who worked really hard and long. They still are not on the Hillary Clinton train. And you know, Bernie Sanders' speech tonight is going to set the tone for the rest of this convention. I was kind of wondering earlier whether he --

COOPER: It's also the -- for those who don't know, it is the culminating speech tonight.

BORGER: Right.

HENDERSON: Right. Right.

COOPER: Everything --

BORGER: But I was kind of wondering whether he was going to say, I don't care about your damn e-mails.

(LAUGHTER)

HENDERSON: Yes.

BORGER: I think in this particular case, he actually does.

HENDERSON: I think one of the difficulties here is that Bernie Sanders basically spent a year portraying Hillary Clinton as a captive of Wall Street, as a captive of the 1 percent. He in some ways delegitimize some of her victories in the south. So I think it's hard to sort of undo that. A lot of Sanders supporters, their identity almost wrapped up in not only being Bernie Sanders supporters but being very anti-Hillary. So I think it's going to take a lot more than a speech and some e-mails to get over this.

COOPER: And yet, so, Michael, I mean, what we heard this morning from Bernie Sanders, he got a lot of applause when he was talking about defeating Donald Trump. It's when he turned to the idea of voting for Hillary Clinton.

MICHAEL SMERCONISH, CNN ANCHOR, "SMERCONISH": And Tim Kaine.

COOPER: And Tim Kaine. That's when the boos began.

SMERCONISH: That it became a flashpoint. My reaction is to say, drama is not necessarily a bad thing. I think it fuels great interest in what's about to unfold. We were just in Cleveland. Day one we had a floor vote. We had the Melania situation when she spoke on Monday night. We had the Ted Cruz situation. And according to CNN/ORC, Donald Trump came out of it just fine. Came out of it with a bump.

The issue with this is that it may have metastasized. There could be some residual issue here if there are more e-mails and if there is a Russian link.

COOPER: And our Donna Brazile has said, point blank, I interviewed her yesterday, she believes there are more e-mails to come and likely more embarrassing information to come.

KING: The reason she got the job is a lot of names floated yesterday, a lot of people close to Clinton were saying let's go to the Housing Secretary Julian Castro. Other people close to Clinton said let's go to the former Michigan governor Jennifer Granholm.

The -- Donna's name came up because people in both camps trust her. A lot of the Sanders people go back to the Jackson campaigns of the '80s with Donna. That's when I first I met her. She is viewed as fair, she is viewed as someone of integrity, she is viewed as someone who understand they want answers and a house cleaning. They may not get as big of a house cleaning as they want, but they'll get some of it and they know they trust Donna inside. That's why she emerged.

I just want it read you this one quick tweet.

COOPER: And by the way, Wolf is going to be talking to her in our next segment.

[17:20:02] KING: Yes. You asked me what's happening here, Jason Noble is a reporter for the "Des Moines Register," interviewed an Iowa delegate earlier today, and who said this, quote, "Bernie basically fed us a bunch of Mountain Dew and now he wants us to go to bed. It's not going to happen." I think that sums up what's happening down there.

HENDERSON: I think that's right. Yes.

MICHAEL NUTTER, CNN POLITICAL COMMENTATOR: I think -- I think John's point is the point. Both sides do trust Donna. And what does she do within a day? Issues an apology on behalf of the Democratic National Committee for what has happened. And I don't know what -- I don't what all the e-mails say and I don't what's to come but clearly condemning behavior, the actions, the language, all of that, needs to be very, very clear, will not be tolerated, is unacceptable. And then how do we bring it all together?

Because at some point in time, you know, we have, as Democrats, and I'm a superdelegate, you need to get about the business from my perspective of defeating Donald Trump. So, I mean, we'll have loud noise, protest, agitation. How do we bring it all together?

COOPER: Bill Press, as a Sanders supporter?

BILL PRESS, CNN POLITICAL COMMENTATOR: I love this. (LAUGHTER)

PRESS: I got to tell you --

COOPER: Yes.

PRESS: When this panel is over, I'm going to get down there, get a sign, I'm a California delegation and I'm going to be chanting. But you know what we're seeing now? First of all, a lot of energy, a lot of enthusiasm. This is like a Bernie Sanders rally. I think the Bernie Sanders people for the moment have taken over this convention.

COOPER: So are you going to be booing once Sanders mentions Hillary Clinton in his speech?

PRESS: No. No, I'm not that extreme. But I think what we're seeing is that the Sanders people really -- they came in here, so did the Hillary people, with a lot of energy. Coming into this and it's been pent up and they're letting it out and I think it is great. And the -- for the Sanders people they won a lot in the platform. They won a lot on the rules committee. Then they got a bump they weren't happy with Tim Kaine, and then they got a bump with these e-mails and so they're even more energized.

And they still want their pound of flesh. And even if their leader Bernie Sanders says, cool it, guys. Cool your jets. Let's not protest. They're not going to take that.

COOPER: Andre, we've been hearing a lot from Donald Trump today about all of this.

ANDRE BAUER, TRUMP SUPPORTER: Anderson, I would say, these Bernie folks did not come here to check their brains at the door. They have been text messaged, they have been talked to by party chairmen. Bernie has actually sent out a text to them. They have been touched in many different ways to ask not do exactly what they are doing.

And if they can't get their message to these people that have been touched that are inside this building, what does it do to the Bernie folks that aren't touched at all that are outside the building? That aren't delegates? That aren't getting this communication through the camp?

CHRISTINE QUINN, FORMER NYC CITY COUNCIL SPEAKER: Well, look, they'll get a big communication tonight when Bernie Sanders speaks to the delegation and when he speaks strongly and clearly about unity. But I have to say, you know, and it kind of goes back to the quote from Donna Brazile about, now you're really going to see, you know, what happens when Democrats have a convention, would anyone want any of this disagreement on the floor tonight? No. But I don't actually think I feel it's a bad thing.

The Bernie people have a lot of pent-up energy for not having won and they're going to express it tonight. We're going to hear Senator Warren, Michelle Obama, Bernie Sanders, and then we're going to move on because one thing -- you know, obviously some of the Sanders people clearly are upset. But what none of the Sanders people want is to do anything at the end of the day that is going to help elect Donald Trump. And that's the message we're going to hear from Sanders.

COOPER: We'll see. We'll see. I mean, you say everyone is going to move on. We'll see if that actual happens in the days to come.

Just ahead, Wolf Blitzer is going to sit down and speak with Donna Brazile, the new chairwoman of the DNC. We're going to continue the conversation about tonight's speaker lineup and more. Back in a moment.

REP. ELIJAH CUMMINGS (D), MARYLAND: He helps himself. The true test is whether he helps those less fortunate. He would say, son, you go to school, to get blessed so you can bless. And that is the standard by which he measured me growing up and it's the standard by which I still measure myself. And it's the standard we Democrats use today.

I stand before you because my parents saw a promise in their seven children, but my parents did not do it alone. No one does it alone. It was our Democratic Party that pushed open the doors of opportunity for me and for millions of children all across this great country. It was our party that fought for Head Start and good schools. And made college affordable and champion Affirmative Action and school desegregation.

That passed Social Security and Medicare, that defended our nation abroad, fought for our veterans back home, that protected the rights and pensions of our workers. And that made the dream of homeownership possible for millions of American families. Yes, it still is our Democratic Party that championed in civil rights and voting rights.

[17:30:09] And voting rights. It's we Democrats who fully understand that when you take away a person's right to vote you take away their ability to shape and determine their own destiny.

(CHEERS AND APPLAUSE)

CUMMINGS: And it was and it is our Democratic Party that fights for women's rights, gay rights, the LGBTQ rights. Our party does not just believe, but understands that Black Lives Matter.

(CHEERS AND APPLAUSE)

CUMMINGS: But we also -- we also recognize that our communities and our law enforcement work best when they work together. Our party -- our party -- our party knows that diversity is not our problem but is our promise. And that's why -- ladies and gentlemen, that's why, ours, ours, is a party of unity and not division.

(CHEERS AND APPLAUSE) CUMMINGS: I'm proud that our party's platform will help not the wealthy, not the 1 percent, but still it will help our struggling middle class, our working families, the disadvantaged and the disabled. It will help the less fortunate. Our platform has passed my father's test and it has done so not by seeking common ground but aspiring to higher ground.

It envisions a nation where we do not merely increase the minimum wage, but we enact a living wage. It envisions a nation in which we eliminate the death penalty because we as Democrats, we value every life, black, white, Asian, every life.

(CHEERS AND APPLAUSE)

CUMMINGS: It envisions a nation where we do not have to choose between protecting the environment and creating jobs but where we can defend our planet against global warming, while at the same time enacting policies that foster job creation, incentivized new start-ups and bring expatriated jobs back home.

It envisions a nation where every child can get a first-rate education and leave school equipped to compete in a global economy. It envisions an America in which we protect a woman's right to choose. Where everyone can get the health care they need when they need it. Regardless of their zip code or circumstance because health care in our country is not a privilege, it is now, thanks to President Barack Obama, our right as Americans.

And so, Madam Chair, when I say my prayers at night, and I look up to the heavens, I see the stars and sometimes I see my father. I know tonight he's smiling on all of us. And he, like me, is proud. Proud of our platform committee. Our truly progressive platform. And our great nominee, Hillary Clinton. And our party's bright future.

(CHEERS AND APPLAUSE)

CUMMINGS: And as my father -- and if my father, that brilliant man with a fourth grade education, but a mind full of wisdom and commonsense was standing here with us tonight, I know he would be proud of all of you.

[17:35:17] And he would say these words, that this election is bigger than Hillary Clinton, bigger than Bernie Sanders, is bigger than all of us.

(CHEERS AND APPLAUSE)

CUMMINGS: It is about generations yet unborn. And he would say -- and he would say these simple words, you are blessed so you can bless others. Go out there and vote, and don't stop lifting up the American people.

May God bless -- may God bless America.

(CHEERS AND APPLAUSE) BLITZER: Speech by Congressman Elijah Cummings of Maryland, introducing the Democratic Party platform. And this crowd clearly very excited by what he said.

Donna Brazile is with us right now. She is now the interim chair of the Democratic National Committee.

Donna, this must have been a big surprise to you, what has happened.

DONNA BRAZILE, INCOMING DNC CHAIR: That's right, Wolf. When I left Cleveland and went home to get a change of clothes to come up here, I thought well, you know, this week I will spend a lot of time with you, Anderson, Don and all of the other great anchors. And as you can imagine, I am the vice chair of the party. And when I received the call yesterday to accept the role and responsibility of interim chair at end of the week, I will do it when Debbie steps down on Friday.

BLITZER: You did something extraordinary just moments ago on behalf of the Democratic National Committee. You issued a formal public apology to Senator Bernie Sanders. Why?

BRAZILE: I thought it was very important. I did it personally. I met with his staff and his entire delegation on Saturday at the Rules Committee. I issued it publicly on television. But I thought I wanted to do it on behalf of the party. And now that the party is coming together in so many ways, I know you see a lot of passion, but this is a Democratic Party convention. We don't silence our voices.

This is an opportunity for people who did not get a minority report on the TPP, the Trans Pacific Partnership. They want to express their views. So -- but I want to go back to that apology. This apology is not just to Bernie Sanders. It is to donors. It is to anyone and everyone that clearly we offended. And the e-mails that were revealed that were hacked.

And we want to get down -- we want to also get to the bottom of the hacking. What happened? The FBI is also investigating.

BLITZER: We know the FBI has issued a statement today saying they are investigating.

BRAZILE: Yes.

BLITZER: But we've also learned, Evan Perez, our justice correspondent, that the DNC e-mail system may have been hacked by whomever, maybe the Russians, for a year. And that the DNC was very slow to respond to warnings that your system was hacked. Is that true?

BRAZILE: I talked to the general counsel of the DNC and he assures me that every step along the way, when we were notified of these issues that we changed systems, changed procedures, but these hackers are so sophisticated that they changed procedures. So yes, it went on for more than a year but at no time did we ignore the warnings from the FBI or any other federal officials.

BLITZER: How do you know it's not still going on?

BRAZILE: Well, let me tell you, I'm not the geek in the family, I'm the organizer. But what I do know is that we have a very terrific team of consultants, former federal cyber security experts who are working with us to make sure we have a very safe system.

BLITZER: It is a pretty -- the substance of the e-mails, as you well know, this is why you apologized, it was outrageous some of these comments made not just by low-level DNC officials but among the highest.

BRAZILE: Wolf, I have known this staff for a long time. They are my friends. I've worked with them. When I was a DNC staffer, I -- I'm incredibly shocked and embarrassed. As you know, we are a party of tolerance. And some of the things that I read just was personally offensive and so I wanted to get out front, the party wanted to get out front, my fellow officers. And I'm glad we took this step.

BLITZER: It was pretty stunning this morning when Bernie Sanders was speaking to his own supporters and all of a sudden, when he said support Hillary Clinton, Tim Kaine, he got a really angry amount of boos and heckling. And he had to pause for a while. You're deeply concerned that this is going to continue tonight.

BRAZILE: You know, I worked for Jesse Jackson in 1984. That was my first convention. And let me tell you something. There were many of us when Reverend Jackson told us it was time to end our campaign to support Walter Mondale and Geraldine Ferraro, you know, we booed that, too. We're like, we're not ready. But, you know, Reverend Jackson said the movement, the movement continues, the campaign has to end.

[17:40:05] There are many -- my delegates here today who will continue the movement to fight injustice, to fight inequality, to work hard, to ensure that we have a real serious climate change program. They have every right. We're going to bring a lot of them along. Some of them may not come along. But we're going to bring a vast majority of these delegates along with us.

BLITZER: Dana Bash reported a little while ago that there has been an active dialogue now between Bernie Sanders and the DNC to try to make sure that it doesn't get crazy out here tonight.

BRAZILE: On Sunday, I spent time in the ball where I head one of the passes, and I went and met with not just Clinton supporters but Sanders supporters. We talked about how we protect this sanctity of this floor. And you know what, they are doing an incredible job. But again, these are Democrats. We're not going to sit and be silent. They are going to be vocal. But you know, tonight they're going to hear from Bernie, they're going to hear from Elizabeth, they're going to hear from Cory, and you know what, they're going to hear from the first lady of the United States.

At the end of the night, you'll see more joyful marches than what I called, you know, sort of like the activists here today.

BLITZER: You see the demonstrations going on outside. BRAZILE: Yes.

BLITZER: Here in Philadelphia. Pretty angry Bernie Sanders supporters. You see the mood in here, you saw what happened earlier today when Bernie Sanders spoke to his supporters. Was that the reason you decided to take this extraordinary step and formally apologize?

BRAZILE: No, that apology, as you know, I started on Saturday. No one asked me to apologize. I did it because I'm a -- I'm a leader and an official of this party. There's no question that we have to do a better job of communicating not just to Bernie Sanders supporters but to our donors and others who are offended. And again I apologize on behalf of the officers and the entire party.

BLITZER: The interim chair, you were the first vice chair of the DNC. Now you're the interim chair.

BRAZILE: My second stint as being interim, do you know that?

BLITZER: Is it --

BRAZILE: The third time is the charm. Maybe I'll get the job one day.

BLITZER: When was the first time?

BRAZILE: When Tim Kaine stepped down to run for the United States Senate. And I was interim for about five weeks and I passed the gavel on to Debbie Wasserman Schultz.

BLITZER: Donna Brazile, our CNN contributor, now the interim chair of the DNC.

BLITZER: Up next, Anderson is back with the panel to talk about all we just heard and a lot more of the breaking news continues right after this.

(COMMERCIAL BREAK)

[17:47:22] COOPER: The Democratic Party platform being presented right now by Paul Booth. Let's listen in.

PAUL BOOTH, MEMBER, PLATFORM DRAFTING COMMITTEE: The Republican platform would not make American great. The Republican platform of pull the rug out from under us. Legalizing discrimination. Cutting holes in the social safety net. Austerity for you and me while the corporate elite and billionaires get special privileges, and more de- regularization, more privatization and union busting at the expense of working families.

That would not make America great. And neither would the gridlock that we've been living with. Americans need a better option. And that's exactly what this bold agenda represents. But words alone are not enough. This platform needs a band-aid from the voters of America.

COOPER: So you have Bernie Sanders supporter talking about what is in the platform. Congresswoman Marcia Fudge is up next. The platform vote is coming up shortly. Barely two hours into day one of the Democratic convention. We've already seen a lot on stage. Outside the hall and behind the scenes, there's plenty to talk about.

You know, Donna Brazile talked to Wolf Blitzer just in the last segment saying that -- confirming that in fact Jeff Zeleny's reporting is correct, that this -- whoever this hacker was, whoever was able to get into the DNC system was in there for more than a year and Donna yesterday had said there may be many more e-mails to come that are going to be embarrassing for the DNC.

KING: And so the question is, if they are being leaked in some nefarious way to try to influence the election by some part, we don't know that. But that is, you know, the suspicion inside the DNC. They are pointing fingers at the Russians and at the Trump campaign. Let's get the facts on all of those issues. But if someone is going to do this, whether it's for mischief or to manipulate an election, we could be getting them the night before a debate. You get some exchange about Hillary Clinton on some policy issue. Who knows.

But I want to say one thing about the interview. Nowadays we send a link. Now someone should send the link of that interview to Debbie Wasserman Schultz. That's what a leader in crisis does. You apologize, you take your lumps, you stand up, you take responsibility, you promise clarity and transparency, and you stand up for what was wrong.

They were trying yesterday to get her to apologize, Debbie Wasserman Schultz, and she said let's do it in the name of the party CEO, let's do it in the name of somebody else on the staff. That's when they realized, forget about it, she has to go because this was turning into a volcano and she would not act on it. Donna is going to take 2 by 4's because now she's in charge and there's still a mess that she has to clean it up. But that was -- I've been friends with her for a long time so people will say you're just talking about a friend, but that's the way you handle a crisis.

[17:50:05] BORGER: Yes. It's easier for her to clean it up because it wasn't her mess, honestly. And -- but she's -- you know, she's doing exactly the right thing. I think the question is, whether the written apology or Bernie Sanders' plea or whips on the floor are going to have any kind of impact this evening.

COOPER: It's interesting because even during Elijah Cummings' speech there, while a lot of people were listening, there were also a lot of people holding up signs for TPP, chanting against TPP.

BORGER: Right.

COOPER: While Elijah Cummings was speaking, which I know a lot of Cummings' supporters feel was very disrespectful.

(CROSSTALK)

SMERCONISH: Well, the night is going to get awfully interesting.

COOPER: Actually Ben Jealous, former head of the NAACP, is speaking right now. A Sanders supporter. Let's listen in.

BEN JEALOUS, FORMER HEAD OF THE NAACP: And I'm proud to be one of the 1900 delegates here tonight from the Bernie Sanders campaign.

(CHEERS AND APPLAUSE)

JEALOUS: Bernie will be here tonight, and as he said to us today, today is our day to begin to unify so we can defeat Donald Trump.

(CHEERS AND APPLAUSE)

JEALOUS: And I'm looking forward to joining him along with all of us to take back the Senate, elect great local and state change makers, defeat Trump and make Hillary Clinton president of these United States/

(CHEERS AND APPLAUSE)

JEALOUS: And I am proud to support this platform, the most progressive platform in the history of our party. It empowers us all to pull together and win big victories at the ballot box and beyond.

You see I hail from the great state of Maryland. We are staying where Democrats have shown that when we all come together as one, we win more, bigger, and better victories faster.

Four years ago when it seemed like reactionary Republicans were stealing everybody's rights everywhere all at once, we in Maryland adopted the motto of the Three Musketeers and said all for one and one for all.

(CHEERS AND APPLAUSE)

JEALOUS: In the year that followed, we abolished the death penalty, passed marriage equality, decriminalized low-level possession of marijuana, passed the Dream Act, expanded voting rights, and passed sensible gun safety reform.

And it is in that same spirit that we present this platform tonight and say to the college students and graduates who are drowning in debt, join us at the ballot box this fall and together we will make college radically more affordable.

(CHEERS AND APPLAUSE)

JEALOUS: To communities devastated by both mass incarceration and murder join us at the ballot box and together we will shift our nation's priorities away from the failed war on drugs and towards rehabilitation and the reincorporation of men and women returning from prison into our economy.

And public safety strategies, not law and order foolishness, but public safety strategies that actually make us safer.

To the hard-working parents who bear that special pain that comes when you realize your family just can't survive on $7.25, we say join us at the ballot box and we will win the fight for $15 and raise the minimum wage from coast to coast to $15 per hour.

(CHEERS AND APPLAUSE)

JEALOUS: And to residents of rural communities and urban areas ravaged by the poisoning of their wells and the water supply, we say join us at the ballot box and we will ensure that your voice is heard, your water is made clean, and our nation shifts away from gas and coal and towards wind and solar.

(CHEERS AND APPLAUSE)

JEALOUS: And to people of good conscience everywhere who are tired.

[17:55:01] Tired of seeing our neighbors abused, scapegoated, and killed because of racism, transphobia, homophobia, and xenophobia, we say join us at the ballot box and together we will move America forward to become the most perfect example of the unity and dignity of the human family that the world has ever seen.

COOPER: Ben Jealous, former president of the NAACP. A Sanders supporter.

We'll be covering all the big moments as they happen. A platform vote just moments away. Day one of the Democratic National Convention in THE SITUATION ROOM tonight. We'll be right back.